Wuqi County of Shaanxi Province, where the vegetation recovering measures have been carried out for years, was taken as the study area. A total of 100 loess samples from 24 different profiles were collected. Total nitrogen (TN) and alkali hydrolysable nitrogen (AHN) contents of the soil samples were analyzed, and the soil samples were scanned in the visible/near-infrared (VNIR) region of 350-2500 nm in the laboratory. The calibration models were developed between TN and AHN contents and VNIR values based on correlation analysis (CA) and partial least squares regression (PLS). Independent samples validated the calibration models. The results indicated that the optimum model for predicting TN of loess was established by using first derivative of reflectance. The best model for predicting AHN of loess was established by using normal derivative spectra. The optimum TN model could effectively predict TN in loess from 0 to 40 cm, but the optimum AHN model could only roughly predict AHN at the same depth. This study provided a good method for rapidly predicting TN of loess where vegetation recovering measures have been adopted, but prediction of AHN needs to be further studied.
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J Environ Manage
January 2025
College of Eco-environmental Technology, Guangdong Industry Polytechnic University, Guangzhou, 510300, China.
Nitrogen-removal promotion is a significant problem when biological nitrogen removal is used to treat ammonium nitrogen (NH-N) wastewater with a low chemical oxygen demand (COD)/NH-N (C/N) ratio. In this work, the biological nitrogen removal capacity of the biological contact oxidation reactor (BCOR) system was enhanced through the enrichment of Acidobacteria. The system was successfully started from Day 1 to Day 50 and stably operated through temperature, pH, and dissolved oxygen (DO) regulation from Day 51 to Day 254.
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School of Nutrition and Public Health, College of Health, Oregon State University, Corvallis, OR, USA.
Background: Billions of dollars have been spent implementing regulations to reduce traffic-related air pollution (TRAP) from exhaust pipe emissions. However, few health studies have evaluated the change in TRAP emissions and associations with infant health outcomes. We hypothesize that the magnitude of association between vehicle exposure measures and adverse birth outcomes has decreased over time, parallelling regulatory improvements in exhaust pipe emissions.
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Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China.
Desertification is a major ecological issue worldwide that results in the destruction of terrestrial ecosystems. Restoration of desertified ecosystems has been carried out in recent decades, but the role of soil microorganisms in this process is poorly understood. Thus, to deconstruct the effects of desertified system restoration on soil microbial communities, we examined the changes in soil characteristics as well as the variations in and drivers of soil microbial diversity and community composition of the Hulun Buir Sandy Land in Northeast China, where restoration activities have been performed for approximately 30 years.
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Key Laboratory for Animal Nutrition and Feed Science of Hubei Province, Wuhan Polytechnic University, Wuhan, 430000, China.
Hydroxycinnamic acid derivatives are a class of phenolic acid compounds, including sinapic acid, ferulic acid, and caffeic acid, which are widely found in plants. This experiment was conducted to study the effects of hydroxycinnamic acid derivatives (sinapic acid, ferulic acid, and caffeic acid) on the growth performance, muscle physical parameters, and intestinal morphology of tilapia. A total of 320 tilapia fingerlings (9.
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Internos carrera de Medicina, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
Unlabelled: Hyponatremia is the most common hydroelectrolyte disorder in hospitalized patients. It is unclear whether there are differences between severe hyponatremia (<125 mEq/L) and very severe hyponatremia (<115 mEq/L) in terms of etiology, response to therapy, and mortality.
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